FILE - In this April 27, 2017, file photo, a police officer wears a newly-issued body camera, part of the first phase of a plan to equip 22,000 officers with body cameras, outside the 34th precinct in New York. Seattle Mayor Ed Murray on Monday, July 17, 2017, ordered the city's police department to equip patrol officers with body cameras, saying he doesn't want any other serious uses of force to go unrecorded. The decision came a month after the absence of video recordings left lingering questions about the police shooting of Charleena Lyles, a pregnant mother who had struggled with mental health issues. (AP Photo/Mary Altaffer, File)

FILE - In this January, 2015, file image from video from a Seattle police body camera video, Seattle police officers move in to make an arrest during a Black Lives Matter demonstration in Seattle. Seattle Mayor Ed Murray on Monday, July 17, 2017, ordered the city's police department to equip patrol officers with body cameras, saying he doesn't want any other serious uses of force to go unrecorded. The decision came a month after the absence of video recordings left lingering questions about the police shooting of Charleena Lyles, a pregnant mother who had struggled with mental health issues. (Seattle Police Department via AP, File)

FILE - In this Thursday, March 12, 2015, file photo, Seattle police officer Debra Pelich wears a video camera on her eyeglasses, part of a pilot program testing the cameras, as she talks with a local citizen before a small community gathering in Seattle. The camera is attached to a battery pack and controls on the officer's uniform. Seattle Mayor Ed Murray on Monday, July 17, 2017, ordered the city's police department to equip patrol officers with body cameras, saying he doesn't want any other serious uses of force to go unrecorded. (AP Photo/Elaine Thompson, File)

The decision, first reported by The Seattle Times , came a month after the absence of video recordings left lingering questions about the police shooting of Charleena Lyles, a pregnant mother who had struggled with mental health issues.

The city has been negotiating with the Seattle Police Officers Guild over deploying the cameras. But Murray said the cameras are a necessary accountability tool and the union talks have stalled.

"Body cameras improve behavior and de-escalation on both sides of the camera," Murray said in a news release. "We have taken far too long to fully implement the body camera program due to legislative gridlock — it is past time to move forward. This order will get cameras on officers on the street, so we know what happens during interactions with the public."

All bike-patrol officers in the West Precinct, which includes much of downtown Seattle, are to begin wearing them by Saturday. The remaining patrol officers in the precinct are to have them by Sept. 30, with other precincts to follow.

The city will continue negotiating with the union over the issue even as the cameras roll out, he said. Guild President Kevin Stuckey said Monday he was confused by the order, calling it unnecessary because both sides are still at the bargaining table.

He said the guild has been bargaining in good faith toward a body-camera program, and that the mayor's action won't create a "sustainable program." Instead, it will lead to a program with "many different holes in it," Stuckey said.

U.S. District Judge James Robart, who is overseeing police reforms under the city's 2012 agreement with the Justice Department, has pushed for the body cameras. He has also said he won't let the union hold the city hostage by linking wage increases to constitutional policing.

Robart was scheduled to hold a hearing in the reform case Tuesday.

Some Seattle officers have previously worn the cameras on a trial basis.

"No one is more committed to equipping officers with body cameras than I am," Chief Kathleen O'Toole said in a written statement. "As studies and our own pilot (program) have shown, body cameras are critical tools, not just for holding all involved to account for their actions, but also to enhance safety of officers and community members."